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Obtaining free disk space

Posted on 1997-11-21
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Last Modified: 2013-12-03
There is a function called GetDiskSize (or Space ?, i don't remember now) which returns values you can use to calculate free space on a disk. But Microsoft claim that this function works wrong on disks greater than 2GB. There is also Ex version of this function which works, but only for NT and Win95 OSR2. So how can I get proper disk size under Win95 for volume greater than 2GB ?
Thanks, Bill G.
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Question by:et
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jhance earned 600 total points
ID: 1408727
The GetDiskFreeSpaceEx function lets you avoid the arithmetic required by the GetDiskFreeSpace function.

Windows 95: 
The GetDiskFreeSpace function returns incorrect values for volumes that are larger than 2 gigabytes. The function caps the values stored into *lpNumberOfFreeClusters and *lpTotalNumberOfClusters so as to never report volume sizes that are greater than 2 gigabytes.
Even on volumes that are smaller than 2 gigabytes, the values stored into *lpSectorsPerCluster, *lpNumberOfFreeClusters, and *lpTotalNumberOfClusters values may be incorrect. That is because the operating system manipulates the values so that computations with them yield the correct volume size.

Windows 95 OSR 2: The GetDiskFreeSpaceEx function is available on Windows 95 systems beginning with OEM Service Release 2 (OSR 2). The GetDiskFreeSpaceEx function returns correct values for all volumes, including those that are greater than 2 gigabytes.




Note that the values obtained by this function are of type ULARGE_INTEGER. Be careful not to truncate these values to 32 bits.

Windows 95 OSR 2: 
The GetDiskFreeSpaceEx function is available on Windows 95 systems beginning with OEM Service Release 2 (OSR 2).
Use the GetVersionEx function to determine that a system is running OSR 2 or a later release of the Windows 95 operating system. The GetVersionEx function fills in the members of an OSVERSIONINFO data structure. If the dwPlatformId member of that structure is VER_PLATFORM_WIN32_WINDOWS, and the low word of the dwBuildNumber member is greater than 1000, the system is running OSR 2 or a later release.

Once you have determined that a system is running OSR 2, call the LoadLibrary or LoadLibraryEx function to load the KERNEL32.DLL file, then call the GetProcAddress function to obtain an address for the GetDiskFreeSpaceEx function. Use that address to call the function.
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by:et
ID: 1408728
Ok, I found the same in MSDN, but it doesn't answer my question which is wrong question ! I asked if one can obtain disk size larger than 2GB under Win95 not OSR2. Simply: you cannot have drives larger than 2GB under Win95 (not OSR2).
To stop disscusion I'll grade jhance, although he actually didn't answer my question just because there is no answer, as I stated above.

Jhance, thanx for looking in MSDN, I also have one :)
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